Oil-burning fire-box



Sept. 8, 1931. R. MODELL OIL BURNING FIRE BOX File d Dec. 7. 192a 3Sheets-Sheet l .1": Enl- MODELL Sept. 8, 1931.

1711! yumm FIRE BOX led Dec.

1928 3 Sheets-Sheet 3 3mm $06M 91600066,

wi/hwao l atent ed Sept. 8, 1931 UNITED STATES ROBERT MODELL, OFSACRAMENTO, CALIFORNIA OIL-BURNING FIRE BOX Application filed DecemberThe invention relates to improvements in furnace fire-boxes and moreparticularly to those which are used in connection with boilers. Oilburners in connection with locomotives, crane engines, steam shovelengines, etc., not only produce excessive smoke under presentconditions, but consume a great deal more fuel than is necessary, bypermitting numerous unburned fuel units to escape.

forming the smoke. Moreover, after the burners are turned off for alength of time and again lighted, the furnaces are prone to back-firedue to ignition of oil left upon the bottom of the fire-box incident tocutting the burners off.

The objects of my invention are to provide a new and improvedconstruction for economizing in fuel and reducing the discharge ofsmoke, and to make provision whereby the bottom of the fire-box cannotbe flooded with oil when the burners are turned off.

With the foregoing in view, the invention resides in the novel subjectmatter hereinafter described and claimed, description being accomplishedby reference to the accompanying drawings.

Fig. 1 is a longitudinal sectional View through the furnace of alocomotive boiler (preferably a passenger or switch engine) showing thenovel construction of the firebox bottom.

Fig. 2 is an elevation of the rear end of the tire-box bottom asindicated by line of Fig. 1.

Fig. 3 is a vertical transverse sectional view through the fire-boxbottom on line 3 3 of Fig. 1.

Figs. 4 and 5 are horizontal sectional views on lines 44 and 55 of Fig.1.

Fig. 6 is another longitudinal sectional View showing the constructionwhich is preferably followed in connection with the fireboxes offreight, crane, steam shovel and analogous engines in which smoking isnot so objectionable.

Figs. 7, 8 and 9 are sectional views on the correspondingly numberedlines of Fig. (3, the brick fire-box bottom being shown in end elevationin Fig. 7.

7, 1823. Serial No. 324,516.

In the form of construction shown in Figs. 1 to 5 inclmive, F denotesthe fire-box of a locomotive boiler B, T has reference to the lire-tubesat the rear end of the lire-box, and l) designates the usual door at thefront end of se -bo. The tire-box bottom 10 is prefers fiat and it iswith the construction of this bottom and the arrangement of thefurl-supply means, that the present invention concerned.

Formed longitudinally within the bottom extcnc. .g substantially fromback to crcof, between its upper and lower no fine 11. Also formedlongiin the bottom 10 at opposite sides of n la-1e l1 and between theupper and lower 3' said bottom, are two flame-return the three tiues11-42 being in comi .n at their front ends by a transverse tpiuuvflue i3which, like the other times, is

formed between the upper and lower of the refractory bottom 10. Twolonnal slots 14' extend from the rear ends runs 12 through the upperside of the bottom 10.

The rear end of the flue 11 has its bottom d'uvnwardly offset, providinga vertical barrier 15, and the portion 16 of said flue bottom vehindsaid barrier, declines rearwardly to an opening 17. A main burner 18extends through the rear wall of the firebox in posit on to direct fueland flame forwardly in the tine 11, and under said main burner, apilot-tanner 15) also extends through said well. This pilot-burner ispositioned in opposed relation with the barrier 15 so that the flameprojected forwardly from said pilothurit-er will strike said barrier andnot only maintain the latter at high temperature, but deflect upwardly,so that as soon as fuel is discharged from the front end of the mainburner 18. it will he vaporized and ignited. When lighting thepilot-burner, it is necesv to insert a quantity of fuel-saturated te orthe like into the opening 17 to iniiially heat said pilot-burner 19. Thepilotburner 19 will be kept burning as long as the boiler is in service.It is to be ignited one hour before the boiler is to be used.

The flame and any fuel units not yet ignited, pass forwardly in the flue11 and as the bottom 10 becomes highly heated, the unburned fuel unitsbecome more and more volatilized, so that by the time the flame hastraveled rearwardly through the flues 11 to the slots 14, all of saidfuel is aflame and the flame is discharged into the fire-box F which isalmost completely filled by said flame. It will thus be seen that aconstruction has been provided which will effect economy in fuel, whichwill be highly efficient, and will be practically smokeless, due to thethorough combustion which takes place.

The construction so far described is preferably used in the boilerfurnaces of passenger and switch engines, in connection with which thesmoke from oil burners is now most objectionable. However, use of thisform of the invention is not restricted to any par ticular form offurnace.

Another advantage for the construction so far described, may beexplained. 'hen the burners 18-19 are turned otf. any oil dischargingtherefrom as the supply finally cut off, cannot pass the barrier 15 andwill drain down the bottom portion 16 of the flue l1, and dischargethrough the opening 17. Hence, there is no quantity of oil loft in theflue to ignite and cause trouble when an attempt is made to again lightthe burners.

The form of construction shown in Figs. 6, 7, 8 and 9 is preferably usedin such EireboXes as those commonly employed on heavy freight engines,crane engines and steam shovel engines. In these views, the ref actoryfire-box bottom 20 is longitudinally channeled and the main andpilot-burners 18a-19a extend through the rear wall of the fire-box abovethe upper side of said bottom. A barrier wall 15a however, is providedacross the rear central portion of the bottom 20 with its upper edgeabove the aXis of the burner 19a, whereas said edge of the barrier wall15a is below the avis of the main burner 18a. Hence, while flame fromthe pilot-burner 19a will strike the barrier 15a, maintaining the latterat high temperature and deflecting upwardly to ignite fuel from theburner 18a, the forward blast of fuel and flame from this main burner184, Will for the most part pass over said barrier. However, some flamefrom the main burner 18a will continually play upon the barrier 15a tomaintain it at high temperature and this is also true in connection withthe burner 18 and the barrier 15 above described. Maintaining thishighly heated part 15 or 154 immediately in advance of the main burnerassists in initially gasifying the fuel and insuring proper combustion.

Behind the barrier wall 15a, is an opening 17a, and a portion of thefire-box bottom 24) behind said barrier, declines to said opening.Hence, any oil dripping from the burners when they are turned off,cannot pass the barrier 15a but is drained out through the opening 17a.Consequently, the bottom 20 annot. be covered with a film of oil toignite and cause a flare-back or back-fire when the furnace is againlighted. \Vhen initially lighting, a quantity of fuel-saturated waste orthe like is inserted into the opening 17 a to initially heat thepilot-burner 19a. 7

The form of construction just described will be highly efficient andeconomical in fuel consumption, but will produce a great deal more smokethan the construction first described. Hence, it is preferable that itbe used only where smoke is not so objec tionable.

On account of the excellent advantages existing from the detailsdisclosed, they are preferably followed. However, within the scope ofthe invention as claimed, variations may be made.

I claim l. A furnace fire box having a refractory bottom, a longitudinalflame flue extending from back to front of said bottom between he upperand lower sides thereof, return flame flues extending longitudinally ofsaid bottom between its upper and lower sides, a tr: nsverse flame fluebetween the upper and lower sides of said bottom placing the front endsof the longitudinal flame flues in communication with each other, andflameescape openings from the rear ends of said flame return fluesthrough the upper side of said bottom; together with a burner mounted atthe rear end of the first named flue for diiecting flame and fuel underpressure into the same.

A structure as specified in claim 1; the rear end of the bottom of thefirst named flue being provided with a downward offset to provide avertical barrier and being rearwardly declined. behind said barrier, anda pilot burner mounted to direct flame against said barrier, saidtire-box bottom having an o iening' at the rear end of said declinedportion of said flue bottom.

In testimony whereof I have hereunto affixed my signature.

ROBERT MODELL.

